Production of a 23S Helium Beam

1 September 1969

journal article
research article
Published by AIP Publishing in Review of Scientific Instruments

Vol. 40 (9) , 1141-1143
https://doi.org/10.1063/1.1684181

Abstract

Beams of metastable helium produced by electron bombardment generally contain atoms in both the 2¹S and 2³S states. It is important in many experiments to distinguish between these states, or at least to know the population ratio. A beam of 2³S and ground state helium atoms has been produced by electron bombardment and subsequent resonant quenching of 2¹S atoms with 2¹S−2¹P 2 μ radiation. This radiation mixes the 2¹S and 2¹P states, the latter decaying primarily to the 1¹S state by emission of 584 Å radiation. The quenching has been studied as a function of beam atom velocity. The results indicate that beams of metastable helium containing less than 1% 2¹S atoms can be produced.

Keywords

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